Readers of this page are probably English speakers, so they should use the first address.

Players can choose any of these languages by sending their email messages to the intended address.

Players with different languages can play each other without any problem. They can set what languages they speak using the standard (ISO 639-2) language codes, so it is easy to find a common language to talk in, if there is one.

Prepare for meeting chess friends from far away countries of the World.

The server is prepared to support more languages to let other players to talk with it in their mother tongue. The languages are managed by language teams. If you feel ambition to help players speaking your language, you can contribute in a language team.
See more on the Volunteering page.
They currently work on different languages, the following new language(s) are coming:

Italian

Spanish

As soon as a team finishes the initial translation phase and there are sufficient volunteer contributors, the language will be officially supported, so everybody can use it.

A number looks very different in other numerical systems.
Here is for example the decimal 58604. In the octal system it is 162354, while in binary it is 1110010011101100.
Sounds much better in the 16th numerical system: E4EC